Separation of racemic mixture of compounds into the respective enantiomers can be of utmost importance in chemistry, and is especially important in the pharmaceutical field, since the different enantiomers of a biologically active compound may display different pharmacological effects. Gas chromatography has been demonstrated to provide a rapid, sensitive, and efficient method for separating enantiomers. Gas chromatographic separation of the diastereoisomeric N-tri-fluoroacetyl-L-prolylamide derivatives of asymmetric amines on an achiral stationary phase is known, as discussed for example by Murano, Agr. Biol. Chem. 37 981- 988 (1973); Halpern, et al. Chem. Commun., 34 (1966); and F. Wegand, et al. Chem. Ber., 90, (1957). Separations of this type are especially useful as a means of quality control in pharmaceutical manufacturing. In the monitoring of the quality of products by such gas chromatographic techniques, it is important not only to effect complete separation, but also to accomplish the separation in a minimal amount of time. It would therefore be advantageous to have resolving agents which could shorten the time necessary to obtain an effective resolution of enantiomers.
It is an object of this invention to provide certain N-perfluoroacyl-.alpha.-amino acid halides which are effective resolving agents for asymmetric amines. The compounds of this invention have the advantage over the heretofore known N-tri-fluoroacetyl-L-prolyl chloride resolving agent of allowing a more rapid gas chromatographic separation of the diastereoisomers formed by the reaction of the acid halides with certain asymmetric amines.